Clamping device



July 30, 1940.

M. A. BELL 2,209,379

CLAMPING DEVICE Filed Dee. 27, 193s 3 Sheets-Sheet l July 30, 1940 M. A. BELL 2,209,379

' CLAMPING DEVICE Filed Dec. 27, 1938 3 Sheets-Sheet 2 Jig). 2.

Marr/5A. 542// July 30, 1940. M. A. BELL GLAMPING DEVICE Filed Dec. 27, 195s 3 Sheets-Sheet 3 @www Marr/5.4.55#

Patented July 30, 1940 PATENT OFFICE CLAMPING DEVICE Morris A. Bell, Oshkosh, Wis., assigner to The Bell Machine Company, Oshkosh, Wis., a corporation of Wisconsin Application December 27, 1938, Serial No. 247,846

9 Claims.

'Ihis invention relates to improvementsin clamping devices, and refers particularly to socalled clamping tables used in the woodworking art for gluing up large articles such as doors and window frames.

It is an object of this invention to provide a clamping device of this general character which is simple in design and construction, and which is readily adaptable to a vwide variety of applications.

Another object of this invention is to provide a clamping device of the character described which is so designed and constructed as to at all times assure an absolutely square clamping action.

In this connection, it is an object of this' invention to provide a clamping device having two I cooperating longitudinal rails movable toward each other in a clamping action in such a manner that absolute parallelism is at all times maintained therebetween.

Another object of this invention is to provide a simple manner of quickly and accurately adjusting the stationary stops with which the power actuated pressure applying members cooperate in the clamping action.

A further object of this invention is to prod vide a clamping device of the character described which is simple and rugged in construction and Well suited for the use for which it is intended.

With the above and other objects in view which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts vsubstantially as hereinafter described, and more particularly dened by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claims.

The accompanying drawings illustrate one *Y complete example of the physical embodiment of looking toward the adjustable stationary stopson the parallel clamping rails;

Figure 4 is a detail sectional view taken through Figure 5 on the plane of the line 4 4;

Figure 5 is a detail sectional rview taken (c1. 144-29'1) j through Figure 2 on the plane of the line 5 5;

and I Figure 6 is a detail view, partly in section and partly in elevation, to illustrate the manner inv which the adjustable stationary stops are secured to the longitudinal rails. y

Referring now particularly to the accompanying drawings in which like numerals indicate like parts, the numeral 5 designates the supporting structure of the clamping device. It comprises two end units, each consisting of a crossbeam 6, preferably having an H-shaped cross section, and two legs 'I rigidly secured to the underside of the crossbeam. These two end units are joined by two castings 8, each of which `is fixed to the underside of one of the crossbeams, and which are bolted together to 'jointly form an X-shaped strut. To further reinforce the supporting structure, the lower ends of th legs are joined by diagonal tie rods 9.

Slidable laterally across the tops of the cross'- beams 6 are two rails IU and II. may be referred toas the adjustable stationary rail, while the rail I I comprises the pressurey applying movable rail. These two rails cooperaten to transversely clamp articles therebetween.

Both of the rails are formed of angle iron sections with a wide horizontal ange I2 and a` narrow vertical flange I3. The flanges I2 l rest directly on the upper surface of the crossbeams 6.

The railV I is held against endwise motion and against displacement from the crossbeams while permitting lateral motion thereof by jibs I4 secured to its undersurface and slidably engaging the lower face of the adjacent ange on the crossbeam.

'Ihe rail II is likewise held in place by jibs I4 secured to the rail and slidably engaging the said ange of the crossbeam.

The adjustable stationary rail I0 is secured in any desired adjusted position by means of ratchet toothed racks I5. fixed to the underside of the inner flanges of the crossbeams 6, and with .whichf pawls I6 carried by the rail engage. The teeth of the racks I5 on the two crossbeams are directly opposite each other, and both of the pawls IB are mounted on a common shaft I'I journalled in bearings I8 depending from the undersurface of the rail IIJ. I'I, it is possible to simultaneously engage and disengage both of the pawls from their respective racks.

The pawls are normally held in operative en-l gagement with their racks by a weightedlever The rail I0- I-Ience, through rotation ofthe shaft I 9 fixed to the shaft which tends to turn the same in a direction raising the pawls to their operative positions. To adjust the position of the rail I0, it is thus merely necessary to lift the weighted lever I9 so as to disengage the pawls and then slide the rail to its desired position. The extent of this adjustment of the rail IIJ is, of course, restricted to the length of the ratchets I5, and is limited in one direction by fixed stops 20 secured to the adjacent ends of the crossbeams.

The movable pressure applying rail II is constrained to a translating motion by racks 2i' fixed to the underside of the rail and preferably part of the jibs I4'. Pinions 22 fixed to the opposite ends of a shaft 23 journalled in bearings 2Q secured to the crossbeams, mesh with the racks 2l, and inasmuch as the racks are directly opposite each other, it follows that any lateral motionof the rail II will be constrained to a translating motion, which is atall times parallel tothe rail I0.

To move the rail II forwardly in a clamping action, an air cylinder 25 is'mounted on the adjacent end of each crossbeam t. The pistons of these air cylinders are connected through arms 26 with the rail I I so that by simultaneously controlling the admission of air pressure to the cylinders, both are active on the rail II with substantially equal force.

The control of the application of air pressure to the cylinders 25 is by means of a foot actuated valve unit, indicated generally by the numeral 2'I. This unit, however, does not form a part of the present invention. It functions in the conventional manner, and its connection. with the air cylinders 25 is deemed clear from the disclosure in Figure 1.

Each rail has an adjustable stationary stop 28 mounted thereon near one end, and an air cylinder 29 adjustably mounted near its opposite end. The pistons of the air cylinders 29 carry pusher members 30 which slide along the horizontal flanges I2 of the rails toward and from the stops 28 to longitudinally compress an article disposed between the rails.

The stops 28 are adjustably securable at different points along the length of the rails by ratchets 3| fixed to the vertical flanges I3 of the rails, and pawls 32 carried by the brackets '$3 which mount the stops 28. The detail of this structure is clearly illustrated in Figure 6.

The two ratchets SI are directly opposite each other so that by engaging the pawls of the stops 28 with the proper teeth, they will be directly opposite.

The air cylinders 29, as stated, are slidable along the length of the rails to increase the range of adjustment of the clamping device and are se cured in adjusted positions in the same manner as the stops 28, that is, through the use of ratchets 3l carried by the rails and pawls 32 carried by the brackets which mount the air cylinders on the rails.

The air cylinders 25 like the cylinders 25 are supplied with air under pressure at the dictation of the control unit 21, but as the manner in which this is effected, forms no part of the present invention, a detailed description thereof is unnecessary.

From the foregoing description taken in ccnnection with the accompanying drawings, it will be readily apparent that this invention provides a practical rugged clamping device suitable for use in the wood-working industry, which because of its novel design and construction is exceptionally flexible in its application, and easily and quickly adjusted to handle any one of a large number of different sized articles.

What I claim as my invention is:

1. A clamping device comprising: a rigid support; a pair of parallel horizontal rails mounted on said support to receive thereon an article to be clamped, one of said rails being laterally movable toward the other; hydraulic means for moving said rail toward the other in a clamping action; a connection between said movable rail and the rigid support to constrain the motion of said movable rail to a translating motion; a stationary stop carried by each of said rails; a cooperating movable stop carried by each of said rails, said stops being adapted to longitudinally clamp an article held between the rails; and pneumatic means for simultaneously forcing said movable stops toward the cooperating stationary stops.

2. A clamping device of the character described comprising: a supporting structure; a pair of parallel rails mounted on the supporting structure, one of said rails being movable toward the other in a clamping action; means for simultaneously applying clamping pressure at opposite end portions of said rails; a connection between said movable rail and the supporting structure constraining motion of the movable rail to a translating motion; a stationary stop adjustably mounted on each of said rails; a movable stop carried 'by each of said rails; and means for simultaneously forcing both of said movable stops toward their cooperating stationary stops.

3. A clamping device of the character described comprising: a rigid supporting structure having horizontal supporting surfaces; a rail mounted on the supporting structure and movable herizontally laterally over the supporting surfaces thereof; adjustable means for securing said rail in a fixed position on the supporting structure; another rail movable horizontally laterally over the supporting structure toward and from the first named rail; a connection between said mov'- able rail and the supporting structure constraining motion thereof to a translating motion parallel with the first named rail; pneumatic means for forcing the movable rail toward the first named rail in a clamping action; a stationary stop carried by each of said rails; a movable stop carried by each of said rails; and pneumatic means for simultaneously forcing the movable stops toward the stationary stops in a clamping action.

4. In a clamping device of the character described: a rigid supporting structure having spaced horizontally disposed. supporting surfaces; a rail movable horizontally laterally across the supporting surfaces of said supporting structure; adjustable means for securing said rail in a xed position; another similar rail movable horizontally laterally across the supporting structure surfaces toward and from the first namedv rail'` means for forcing said second namedv rail toward the first named rail in a clamping action; and'v means for constraining motion of the second named rail to a translating motion comprising, spaced racks carried by the movable second named rail, a pinion meshing with each of said racks, and a single shaft journalled in bearings carried by the supporting structure andy to which each of said pinions is secured.

5. In a clamping device of the character described: a rigid supporting structure including spaced parallel horizontal crossbeams; a pair of parallel clamping' rails, each horizontally laterally movable over said crossbeams; a ratchet xed to each of said crossbeams; a pawl engageable with each of said ratchets; common means mounting both of said pawls from one of the longitudinal rails, whereby said rail is readily secured in an adjusted stationary position; means for forcing the other rail toward the stationary rail in a clamping action; and means for constraining motion of said last named rail to a translating motion comprising, a rack carried by the rail at each end thereof, a pinion meshing with each of said raam, and a single shaft journalled in bearings carried by the crossbeams.

6. In a clamping device of the character described: a rigid supporting structure including, spaced parallel horizontal crossbeams; an adjustable stationary rail horizontally slidable laterally over said crossbeams; means for releasably securing said stationary rail to the crossbeams in any one of a number of different positions of adjustment; a movable rail horizontally slidable laterally over said crossbeams toward and from the adjustable stationary rail; a pneumatic pressure applying device mounted on each of said crossbeams and connected with said movable rail for forcing the movable rail toward the adjustable stationary rail in a clamping action; and means for constraining the movable rail to a translating motion comprising, a meshing rack and pinion connection between said movable rail and each of said crossbeams. 4

7. In a clamping device of the character described: a rigid supporting structure including, spaced parallel horizontal crossbeams; an adjustable stationary rail laterally horizontally slidable over said crossbeams; means for securing j sponsive means for normally holding said shaftr vand consequently the pawls attached thereto in an operative position; a movable rail horizontally slidable laterally over -said crossbeams toward and from the adjustable stationary rail; means for forcing the movable rail toward the adjustable stationary rail in a clamping action; and means for constraining motion of the movable rail to a translating motion.

8. In a clamping device of the character described: a rigid supporting structure including, spaced parallel crossbeams; an adjustable stationary rail laterally slidable over said crossbeams; means for securing said adjustable stationary rail in a fixed positiony on the crossbeams comprising, a ratchet mounted on an undersurface of each of said crossbeams; a shaft extending longitudinally Aof said rail and journalled in bearings depending downwardly therefrom; a pawl mountedon each end of said shaft to engage the adjacent ratchet; gravityresponsive means for normally holding said shaft and consequently thepawls attached thereto in an operative position; a movable rail slidable laterally over said crossbeams toward and from the adjustable stationary rail; means for forcing the movable rail toward the adjustable stationary rail in a clamping action; and means for constraining motion of the movable rail to a translating motion comprising, spaced racks carried by the movable rail, a pinion meshing with each rack, and a shaft journalled in bearings carried by the crossbeams and to which said pinions are secured.

9. In a clamping device of the character described: cooperating stationary and movable rails for supporting an article thereon and to transversely clampthe article therebetween; a stationary stop adjustably secured to each of said rails near one end thereof; a pneumatic pressure applying unit adjustably mounted on each rail near its opposite end; and movable stops actuated by said pressure applying units along said rails and toward the stationary'stops to longitudinally clamp an article positioned between the rails.

MORRIS A. BELL. 

